It is generally accepted that the recreational sport of skateboarding developed as an offshoot of surfing sometime in the late 1960s. As such, the skateboard was, and still is, intended to provide a similar athletic experience to surfing. In recent years, the sport of skateboarding has become popular throughout the industrialized words. This acceptance of the sport is due in large part to technological developments which have improved the ride and handling of skateboards so that they better approximate the smooth side of a surfboard on water.
In its most common current form, a skateboard typically includes a board 6-12 inches wide and 2-3 feet long. Boards are often made of wood or fibreglass. Two sets of two polyurethane wheels are typically mounted on the bottom side of the board, one set of wheels being attached towards the front end of the board, the other set of wheels being attached towards the rear end of the board. Such set of wheels is typically mounted on an axle in a pivoting truck assembly. The truck resiliently pivots about its connection with the board and thereby displaces the axle from its usual orientation perpendicular to the median longitudinal axis of the skateboard. The axles are displaced by tilting the board so that the axles each come to lie on a radius of a circle, thereby orienting the wheels so that they steer the skateboard along the circumference of the circle. This arrangement of wheels provides favourable cornering characteristics along with stability, enabling skilled skateboarders to negotiate smooth, sharp turns in rapid succession.
At one time, roller skates were commonly provided with trucks similar to the trucks found nowadays on most skateboards. Typically, roller skates of this design had two sets of two wheels mounted on pivoting trucks, with the four wheels being disposed essentially at the corners of a rectangle. This old design has given way in popularity recently to an in-line roller blade configuration, with a plurality of wheels arranged along the median longitudinal axis of the roller skate. An in-line arrangement of wheels provides for more speed and manoeuvrability than the rectangular arrangement of wheels on pivoting trucks. However, the in-line configuration naturally sacrifices a degree of stability to achieve improved manoeuvrability.
A variety of skateboard designs have appeared in which an in-line wheel configuration has been adopted. U.S. Pat. No. 5,419,570 issued May 30, 1995, to Bollotte discloses a skateboard having in-line wheels. U.S. Pat. No. 4,382,605 issued May 10, 1983 to Hegna discloses an arrangement of steerable in-line wheels that may be adapted for use on a skateboard. Similarly, U.S. Pat. No. 3,622,172 issued Nov. 23, 1971 to Turf Ski, Inc. shows a land skier with a plurality of in-line ball bearing rollers. The disadvantage of reduced stability that characterizes in-line roller blade skates is accentuated when an in-line configuration is used on a skateboard. With roller blade skates, a user is at least able to balance on two skates that are laterally disposed. With an in-line skateboard, there is no such opportunity to off-set the inherent instability of an in-line design.
There is a need for a skateboard design that combines the speed and manoeuvrability of an in-line wheel arrangement with the handling and stability of laterally disposed wheels. It would be advantageous if such a design exhibited handling characteristics that better mirrored the handling of surfboard on water.